Wire drawing machine



Sept. 12, 1950 E. w. ERTNER 2,521,838

WIRE DRAWING MACHINE Filed April 1, 1948 11/11 111 II III 1 I I PatentedSept. 12,1950

WIRE DRAWING MACHINE" Edward W. Ertner, Berwyn, 111., assignor WeaternElectric Company, Incorpo ated, New York,

N. Y., a corporation of New York Application April 1, 1948, Serial No.18,340 I 2 Claims. (Cl. 205- 22) This invention relates to wire drawingmachines and more particularly to a capstan driving arrangement for sucha machine employing a plurality of individually motor driven capstansfor drawing a wire through successive wire reducin dies.

The features of this invention have been found particularly useful inmachines of the above-referred-to type, during wire stringingoperations, wherein the leading end of a wire to be drawn through themachine is first strung through the several reducing dies by the drawingcapstans. This operation necessitates frequent starting and stopping, inunison, of the individual capstan motorswhich are connected to a commonsource of power until the wire has been strung through each die andthereafter the motors, when brought to full speed, operate at desireduniform speeds with the capstans in step. Due to the individualoperating characteristics of the motors that do not have identical loadsand which are operated from a common source of power, it has not beenpossible heretofore to operate the motors at the desired uniform speedswith the capstans in step, since their acceleration and deceleration isnot uniform. This has resulted in a great deal of wire breakage duringthe wire stringing operation. This wire breakage occurred because themotors would not permit the capstans to supply the wire to successivedies as required.

An object of the invention'is the provision of a simple and efficientdriving arrangement for the capstans of a wire drawing machine duringthe wire stringing operation which will avoid the above-mentioneddisadvantages.

In accordance with one embodiment of the invention, as applied to a wiredrawing machine employing a plurality of feeding capstans eachindividually driven by an induction motor, wherein the motors, whenbrought to full speed, operate at approximately the same speed and areconnectible to a common source of power, each capstan being operativelyconnected to one end of its rotor shaft and arranged in upper and lowerhorizontally aligned pairs, there is fixed to the the lower set ofcapstans ll-l 'l.

opposite end of each of the rotor shafts a sheave.

Other objects and advantages of the invention will more fully appearfrom the following detailed description takenin conjunction with theaccompanying drawing, in which Fig. l is a fragmentary side elevationalview, partly in section, of a wire drawing machine embodying thefeatures of the invention;

Fig. 2 is a vertical sectional view taken on the line 2-2 of Fig. 1; andI 1 Fig. 3 is a wiring diagram showing one embodiment of connections forcontrolling the capstan driving motors from a single source of power.

Referring to the drawing, and particularly to Fig. 1, wherein there isillustrated, fragmentarily,

the upper portion of a wire drawing machine,

there is shown .one embodiment of this invention, Portions of aframework of the machine are indicated in general at Iii for supportingthe various elements of the machine including wire drawing compartmenti2, which includes a front wall and door (not shown), an intermediatewall i3, and a rear wall or removable panel ll.

Arranged within the compartment l2 are two pairs of stepped capstansIl-ll, disposed in upper and lower aligned sets, each capstan beingprovided with a plurality of wire engaging surfaces of graduallyincreasing diameters-in the present embodiment four differentdiametersthe dimension of each capstan diameter depending upon theamount of reduction in the diameter of the wire produced in drawing thewire through a plurality of drawing dies (not shown), also mounted inthe compartment 12. Each capstan i1 is individually driven, in aclockwise direction, as viewed from the front of the machine, or in acounterclockwise direction, as viewed in Fig. 2, by individual threephase squirrel cage induction motors ll-IB operatively connected to theupper set of capstans and three phase squirrel cage induction motorslQ-IS operatively connected to The upper motors i8--i8 are rigidlysuspended from a pair of channel-shaped supports 20, and the lowermotors i9-l9 are rigidly supported upon a pair of channel-shapedsupports 2|, the supports 20 and 2| being suitably carried upon theframework of the machine.

In the present application of the invention, each of the motors i8i8 and|9i9 are operated at approximately the same speed; namely, 1800 R. P. M.from a common source of power, the upper motors II-ll each having a gearhead 22 whereby output shafts 24 thereof, shown at the left-hand end ofthe motor (Fig. 1) and arranged concentric with the rotor shaft, aredriven at 367 R. P. M. Fixed to the output shafts 24 are the two uppercapstans [1-4 I, which thus are rotated at the speed of the outputshafts. The two lower capstans 11-" are directly connected to thelefthand ends of rotor shafts 26 (P18. 1) of the motors 18-" and thusare rotated. at the speed of the rotor shafts of their motors.

Fixed to the right hand end of each rotor shaft (Figs. 1 and 2) of themotors ll-ll and IS-ll is a sheave 26, all of the sheaves being of thesame diameter and provided with V-shaped peripheral grooves 21.Encompassing the four sheaves 26 and frictionally engaged in theperipheral grooves 21 thereof is a, belt 28 of V-shaped cross-section.

In order to provide a desired constant tension on the belt 28, there isprovided a roller 30 journalled on the free end of a supporting arm 3|,pivoted at 32 to a wall 33 of the compartment II. The

roller is yieldably drawn against the upper course of the belt 28 as ittravels between the two upper capstans llll, by means of a tensionspring 34, having its opposite ends attached to the arm 3i at 31 and at38 to a lug 39 fixed to the framework of the machine.

In Fig. 3, a common three phase source of power for the capstan drivingmotors |8--l8 and 19-! is indicated at 40, the motors in thepresent'embodiment being illustrated as of the three phase squirrel cageinduction type. The motors are simultaneously connectible to the sourceof power All by means of a switching means ll, which may be a three-polesingle throw switch. a

The above-described arrangement for coupling the rear ends of the rotorshafts of the motors i8-i8 and 19-49 by means of the sheaves 26 and thebelt 28 is of particular advantage during wire stringing operations onwire drawing machines of the above-described type. In such operations,the motors are intermittently started and stopped in unison as theleading end of the wire to be drawn through the machine is strungthrough the several reducing dies (not shown) in succession inpreparation for regular wire drawing operation. Theoretically, themotors ll-il and I 9I 9 should each operate at the same speed, in thepresent example, 1800 R. P. M., but due to the individual differentoperating characteristics of th motors, plus the fact that the are notidentically loaded, this desired uniformity in speed is not possibleduring intermittent starting and stopping operations. Under theseconditions and without the coupling of the'rear ends of the rotor shaftsof the motors together in the manner described above, the capstans il-llwill operate out of step. By coupling the rear ends of the rotor shaftsof the motors 18-" and |9-|9.

i 4 together by means of the eaves fl and belt 2|, the speeds of themotors, uring th wire stringing operations, which requires intermittentstarting and stopping of the motors, are substantially quired, with theresult that ire breakage is eliminated.

It is to be understoodthat the above-described arrangements are simplyillustrative of theapplication of the principles of the invention.Numerous other arrangements may be readily devised by those skilled inthe art which will embody the principles of the invention and fallwithin the spirit and scope thereof.

What is claimed is:

1. A capstan drive comprising a plurality of electric motors, a capstanfor each motor, means for connecting the motors to a source of power todrive them at approximately the same speed, said motors having theirrotor shafts extending at opposite ends therefrom, one end of each shaftbeing operatively connected to its capstan, a sheave fixed to theopposite end of each shaft, and a belt frictionally engaging andencompassing said sheaves effective during intermittent starting andstopping of said motors to cause the capstans to accelerate anddecelerate in step.

2. A capstan drive comprising a plurality of electric motors, a capstanfor each motor, means for connecting the motors to a source of power todrive them at approximately the same speed, said motors having theirrotor shafts extending at opposite ends therefrom, one end of each shaftbeing operatively connected to its capstan, a sheave fixed to theopposite end of each shaft, a belt frictionally engaging andencompassing said sheaves effective during intermittent starting andstopping of said motors to cause the capstans to accelerate anddecelerate in step, and,means for tensioning said belt.

, EDWARD W. ERTNER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES'PATENTS

